The US electronics store chain Best Buy has put its plans to open several megastores on hold as the business expects losses of up to £45m this year. Photograph Matt Stroshane/Getty Images

The promise was to bring the best of US-style service culture to a market which had become notoriously bad at helping customers make the most of the proliferation of gadgets in our homes.

But as the three-year anniversary of Carphone Warehouse's tie-up with Best Buy approaches, and with just six British stores to its name, the US electricals powerhouse's plan to conquer the UK still looks like a pipe dream. The venture is predicted to rack up losses of up to £55m next year, on top this year's forecast of up to £45m, and the track record to date has been one of disappointment, with delayed store openings and several top-level departures, culminating in a shake-up last week that saw Carphone veteran Andrew Harrison supplant Scott Wheway as chief executive of Best Buy Europe.

Wheway said that he was "delighted" to be heading back into the bowels of Minnesota-based Best Buy, where he would continue to offer "strategy and policy advice", but one industry insider suggested the fledgling retail chain was "miles away from its plan". The source said: "The original plan has failed and now they are trying to think of a new one."

Harrison bats away any suggestion that his job will be to firefight: "I am not ripping everything up and changing what we are doing. I worked with Scott as part of a team. We have gone through the pain of getting the business off the ground and that has been a massive achievement."

He is keen to point out that there is much more to its partnership with Best Buy than establishing the new brand here: Carphone has helped it to make big strides with its mobile business in the US and in turn has been given access to its expertise in consumer electronics.

There had been speculation that the new retailer would give up on opening so-called "big box" stores of between 30,000 to 35,000 sq ft, which put it at loggerheads with established UK chains Currys and Comet. Harrison says that is not true: five stores are pencilled in for next year within that size range. Best Buy has also launched a UK website which Harrison said gave it national reach.

In the US, Best Buy has differentiated itself in a crowded market by creating stores with a relaxed atmosphere, where staff known as "blue shirts" soothe customers' "techno stress", but the two-year delay between announcing plans to enter the UK and actually doing so has given the incumbents the chance to raise their game. Kind-hearted analysts say it is logical that Best Buy should take its time as a common retail problem these days is having too many stores, but Bryan Roberts, director of retail insights at Kantar Worldpanel, says: "Best Buy has made a pig's ear of its market entry … they gave Dixons and Comet two years to get their act together."

Harrison declined to give a break-even target for the business but prefers to think of its projected losses as "investment" in the future. "We have a stable management team and know what we want to do and have to do. We have got a national presence with a web platform and you are going to see us make a much more signficant impact in the coming months."

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